Skimmer scoop



R. R. DOWNIE SKIMMER SCOOP Filed Sept. 50, 1953 20 through the guide roller of Fig. 3..:

' 55 line (not shown) attached to the scoop. Elevariers, so that there is no rocking movement, and 55 Patented Feb. 12, 1955` l l Robert Rex Downie, Beaver Falls, Pa., assigner to KeystonefDriller' Company, Beaver Falls, Pa., a corporation of PennsylvaniaV .f1 f

Application september 30,1933, serial No. 691,71

teams. (c1. 2144-102)A f l This invention relatesto skimmer scoops and tion of the boomgis accomplished by a hoisting effects certain `improveniente over the skimmer line (not shown), and side swinging of the boom scoop disclosed in Patent No. 1,536,390 dated May is effected by a third line or other power-actu- 5,1925, as more particularly pointed out in thev ated mechanism, to vdischarge thespoil gathered present specicationdescribing a preferred emby the scoop. Vbodiment ofthe invention. The scoopismoved backwardly preferably by Intheaccompanying drawing forming apart the action of gravity, which is effective when the ofthis specification,- .l boom is elevated a few feet. vv Duringexcavating, .i .lig.V lis aside` elevationof the improved s kimthe major normal forcestran'smitted to the boom mer scoop shown-carried upon a boom, onlyf part are generally verticaL-but both hoisting and haul- 10 ofwhich-gis shown; f v ing efforts against eccentric or unbalanced resist- Fig. '2 is a fragmentary elevation showing part ances produce severe boom-twisting and laterally ofthe scoop carrying mechanism viewed from the deecting reactions. i Eccentric or unbalanced boom-sidethereof,` thebail being shown in secresistances arise whenever (l) either the hauling l5 tion;Y C Y eort or the hoisting effort is resisted by an ob- 15 Eig is afragme tary cross-section on an er1- stacle` or relatively hard material at one side of 'larged scaleshowing-one 'ofthe guide rollers and the forward jor cutting edge of the scoop; also adjacent parts;` and 1 L V i. (2).. whenever'the center of gravity of the load `Fig, 4 is a vertical section on a still larger scale in the scoop is to one side of the medial vertical l plane of the scoop; also (3) Whenever the scoop 20 'Referring particularlyto the drawing, vthere is is swung by power `while gathering materiaL as shown a boom 5 which (asis known .in the art frequently occurs in the. cleaning upl of a cut. vandhence `renuiresno illustration) consists of Prior to this invention, no durable means have two spacedjbeams rigidly secured -togetherand been provided in roller-mounted scoops for the providing trackways for the supportingrollers of transmission of theseV twisting and laterally de- 2c a skimmer scoop.` The scoop per se notall of fleeting forces. which is shown) is designated by.6,- and is Asup- Mounted on each equalizing rollercarrier 10 ported 'by a .bail` 7 extending crosswise over its is aguide roller 15 rotatable on a vertical pin 16 top at vthe forward or digging end gfalso bya pair which is heldbyrlugsor ears 1' 7 projecting lat-V of links 8 (only one being shown) adjustably conerally from carrierlO. A locking piece or key 18 30 nected tothe' rear end of the scoop. secured yto tl 1e upper ear 17V by a screw (not Extending upwardly from and preferably in-V shown) and passed through a notch 19 in the tegral with the bail 7 are two arms 9 which are side of pin 16 prevents longitudinal movement of spaced apart sufciently to straddle the boom. said pin, yet permits removal of the pin if the Centrally pivoted on the arms 9 are the equalizguide roller or its bearings 20 are to be repaired 35 ing roller carriers 10 on the ends of ,which are or replaced. Disks 21, 22 closethe ends of the rollers 1l which travel along the trackways 5d guide rollers and retain the grease or oil and provided by the boom.V While the trackways 5a also serve as spacers. The peripheries of the are shown as extending along the 'sides of the guide rollers extend beyond the ends of ears 17 40 boom, obviously they could be provided along the and also lie closer to the boom than'the side 40 130D and bOttOm Of the boom, as is known in the faces of the scoop-carrying rollers, so that any art. Links 12 are connected at their forward reaction tending to deflect the scoop laterally or ends tothe equalizine roller carriers 10 and exto twist it on the boom is transmitted directly to tend rearwardly along the trackways for connecthe boom through the guide rollers and not tion with roller carriers 13 on which the rear through the scoop-supporting rollers. The guide 45 rOlleIS 14 are IOtatably mOU-Ilted- The upper ends rollers, their bearings and their supports are of of links 8 are also connected to the rear roller heavy construction, so that the severest reversing Carriers 13. stresses will be transmitted without breakage.

The parts S0 far described areessentially the It will be observed that the guide rollers 15 same as the construction disclosed in the aforerotate on vertical axes which lie in the vertical 50 said Patent No. 1,536,390. plane passing through the pivots of the equaliz- In the operation of a skimmer scoop, the scoop ing roller carriers l0. Thus the guide rollers l5 is pulled along the boom into the earth or other are midway between the ends of carriers 10 and material being excavated by means of a hauling are located at the aXis of oscillation of said carso that both rollers 11 are held out of contact with the webs of the boom.

Located to the rear of the scoop-carrying structure are two additional guide rollers 23 rotatable on pins 24 secured in lugs or ears 25 projecting inwardly from each rear roller carrier 13. Guide rollers 23 are exactly like guide rollers 15 and hence need no further description. Preferably guide rollers 23 are between the rear ends of links 12 and the rear rollers 14, although they could be otherwise located, and they are substantially in contact with the webs of the boom to prevent contact of the side faces of rear rollers 14 with said webs.

The invention attains a number of important results. First, the force effective upon the work is increased by a material reduction in the friction between the scoop-supporting means and the boom, whenever the work is eccentrically engaged by the scoop. Second, the abrasion or wear on the boom webs is greatly diminished and hence the life of a boom is greatly prolonged. Third, the life of the scoop-carrying rollers is considerably increased. Fourth, (with a twopower-line control) the scoop drifts or runs back much more rapidly, and hence the boom` need not be elevated so high to effect backward running, which results in a saving in power and a quicker operating cycle.

While the preferred embodiment of the invention is shown used with a boom having trackways or channels on the sides, obviously it could be used with booms having channels on the top and bottom of the boom, or on the bottom alone in combination with flanged main supporting rollers; hence the claimsare not to be considered as limited to trackways located on the outside of the boom between the top and bottom thereof.

Obviously the invention may be embodied in several forms not shown or described.

Having described one embodiment of my invention, what I claim as new and desire to secure by Letters Patent is:

1. In combination with a skimmer-scoop of the type having a pair of rollers on each side of the boom supporting the forwardV end of the scoop and a'single roller on each Vside of the boom supporting the `rear end of the scoop, a roller mounted on a vertical axis between each pair of forward rollers; another roller also on a. vertical axis slightly forward of each rear roller; and

means carried by the scoop for immovably positioning all said rollers having a vertical axis so that their peripheries are permanently closer to the webs of the boom than the side faces of the scoop-supporting rollers.

2. A skimmer scoop comprising, in combination, a scoop; a bail attached to and extending crosswise of and above the scoop; a pair of equalizing roller carriers pivotally mounted on the bail to swing in vertical planes about a common horizontal axis which is above the bail; a pair of rollers on the ends of each equalizing roller carrier; a link extending rearwardly from each equalizing roller carrier; a rear roller carricr connected to the rear end of each link; a

roller on each rear roller carrier; all of said rollers being freely rotatable about horizontal axes and being adapted to travel along the beams of an excavator boom; a guide roller on each equalizing roller carrier and rotatable on a vertical axis which intersects the horizontal axis of the equalizing roller carrier; a second guide roller on each rear roller carrier slightly forward of the rear roller and also rotatable on a vertical axis; both guide rollers'being so constructed and arranged that they contact with the boom to transmit side thrusts and reactions on the scoop to the boom.

3. In combination with a skimmer scoop and boom-supported carrying structure therefor which is rigidly fixed to the scoop and extends above the same, a plurality of lateral guide rollers adapted to bear against the boom at points well spaced apart longitudinally of the scoop, said guide rollers being mounted on said scoop-carrying structure and projecting inwardly toward the boom farther than any other parts of said scoopcarrying structure so as to make first contact with said boom responsive to any component of force moving or tending to move the scoop sidewise in either direction.

4. In combination with a boom having spaced vertical webs, a skimmer scoop and a carrying structure Vfixed to the scoop and adapted to travel along the boom, a plurality of lateral guide rollers mounted on said carrying structure on each side of the boom and each being rotatable on fixed transverse axes which are parallel to the vertical webs of the boom; the peripheries of said lateral guide rollers being substantially in contact with said webs.

ROBERT REX DOWNIE. 

